To fetch multiple grids in a single query, the QueryMultiple method is used. This then allows you to retrieve each grid sequentially through successive calls against the GridReader returned.
var sql = @"select * from Customers where CustomerId = @id
select * from Orders where Cust...
Sometimes, you want to do the same thing multiple times. Dapper supports this on the Execute method if the outermost parameter (which is usually a single anonymous type, or a domain model instance) is actually provided as an IEnumerable sequence. For example:
Order[] orders = ...
// update the tot...
Open Visual Studio
In the toolbar, go to File → New Project
Select the Console Application project type
Open the file Program.cs in the Solution Explorer
Add the following code to Main():
public class Program
{
public static void Main()
{
// Prints a message to the conso...
string fullOrRelativePath = "testfile.txt";
string fileData;
using (var reader = new StreamReader(fullOrRelativePath))
{
fileData = reader.ReadToEnd();
}
Note that this StreamReader constructor overload does some auto encoding detection, which may or may not conform to the ...
C# allows user-defined types to overload operators by defining static member functions using the operator keyword.
The following example illustrates an implementation of the + operator.
If we have a Complex class which represents a complex number:
public struct Complex
{
public double Real ...
Initialize a collection type with values:
var stringList = new List<string>
{
"foo",
"bar",
};
Collection initializers are syntactic sugar for Add() calls. Above code is equivalent to:
var temp = new List<string>();
temp.Add("foo");
temp.A...
Double Quotes inside verbatim strings can be escaped by using 2 sequential double quotes "" to represent one double quote " in the resulting string.
var str = @"""I don't think so,"" he said.";
Console.WriteLine(str);
Output:
"I don't think s...
Adding the volatile keyword to a field indicates to the compiler that the field's value may be changed by multiple separate threads. The primary purpose of the volatile keyword is to prevent compiler optimizations that assume only single-threaded access. Using volatile ensures that the value of the ...
An interface is used to enforce the presence of a method in any class that 'implements' it. The interface is defined with the keyword interface and a class can 'implement' it by adding : InterfaceName after the class name. A class can implement multiple interfaces by separating each interface with ...
public class Animal
{
public string Name { get; set; }
}
public interface INoiseMaker
{
string MakeNoise();
}
//Note that in C#, the base class name must come before the interface names
public class Cat : Animal, INoiseMaker
{
public Cat()
{
Name = "Ca...
var persons = new[]
{
new {Id = 1, Name = "Foo"},
new {Id = 2, Name = "Bar"},
new {Id = 3, Name = "Fizz"},
new {Id = 4, Name = "Buzz"}
};
var names = persons.Select(p => p.Name);
Console.WriteLine(string.Join(",", names....
var oneNumber = new[] {5};
var theOnlyNumber = oneNumber.Single();
Console.WriteLine(theOnlyNumber); //5
var numbers = new[] {1,2,3,4,5};
var theOnlyNumberSmallerThanTwo = numbers.Single(n => n < 2);
Console.WriteLine(theOnlyNumberSmallerThanTwo); //1
The following throws Invalid...
var oneNumber = new[] {5};
var theOnlyNumber = oneNumber.SingleOrDefault();
Console.WriteLine(theOnlyNumber); //5
var numbers = new[] {1,2,3,4,5};
var theOnlyNumberSmallerThanTwo = numbers.SingleOrDefault(n => n < 2);
Console.WriteLine(theOnlyNumberSmallerThanTwo); //1
var theOnl...
Enumerable.Select returns an output element for every input element.
Whereas Enumerable.SelectMany produces a variable number of output elements for each input element. This means that the output sequence may contain more or fewer elements than were in the input sequence.
Lambda expressions passe...
var names = new[] {"Foo","Bar","Fizz","Buzz"};
var thirdName = names.ElementAt(2);
Console.WriteLine(thirdName); //Fizz
//The following throws ArgumentOutOfRangeException
var minusOnethName = names.ElementAt(-1);
var fifthName = names.ElementAt(4);
...
public interface IAnimal
{
string Name { get; set; }
}
public interface INoiseMaker
{
string MakeNoise();
}
public class Cat : IAnimal, INoiseMaker
{
public Cat()
{
Name = "Cat";
}
public string Name { get; set; }
public string M...
